Automated endoscope reprocessor connection integrity testing

ABSTRACT

A method detects proper connection of fixtures to one or more channels in an endoscope during a cleaning or disinfection procedure. The endoscope has a first opening into one of its channels. The method includes the steps of placing the endoscope at the first opening in a liquid while leaving a gas within the channel, drawing a vacuum on the gas through a second opening into the channel and thereby drawing some of the liquid into the channel, and detecting for air leaking into the channel.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to the decontamination artsincluding the sterilization arts. It finds particular application inconjunction with the decontamination of medical devices, especiallymedical devices such as endoscopes and other devices having channels orlumens that must be decontaminated after use.

[0002] Endoscopes and similar medical devices having channels or lumensformed therethrough are being used on an ever increasing basis in theperformance of medical procedures. The popularity of these devices hasled to calls for improvements in the decontamination of these devicesbetween use, both in terms of the speed of the decontamination and theeffectiveness of the decontamination.

[0003] One popular method for cleaning and disinfection or sterilizationof such endoscopes employs an automated endoscope reprocessor which bothwashes and then disinfects or sterilizes the endoscope. Typically such aunit comprises a basin with a selectively opened and closed cover memberto provide access to the basin. Pumps connect to various channelsthrough the endoscope to flow fluid therethrough and an additional pumpflows fluid over the exterior surfaces of the endoscope. Typically, adetergent washing cycle is followed by rinsing and then a sterilizationor disinfection cycle and rinse. Various connections must be made to theendoscope to achieve flow through its channels. If any of theconnections leaks the process may not work properly possibly leaving theendosope contaminated. Typically, such automated systems check forblockages in the channels, but such testing can be fooled if one of theconnections is not tight.

SUMMARY OF THE INVENTION

[0004] A method of detecting proper connection of fixtures to one ormore channels in an endoscope according to the present inventioncomprises the steps of:

[0005] placing a first opening into at least one of the one or morechannels into a liquid;

[0006] having a gas within the channel;

[0007] drawing a vacuum on the gas through a second opening into thechannel and thereby drawing some of the liquid into the channel;

[0008] detecting for air leaking into the channel.

[0009] Preferably, the step of detecting for air leaking into the atleast one channel comprises monitoring the pressure within the channel.If it falls below a given amount in a given time period an indicationcan be given that the channel is leaking.

[0010] When the endoscope has two channels and where one of the fixturesseparates theses channels from each other internally, the methodpreferably further includes the step of individually testing each of thetwo channels so as to detect gas leaking past the fixture whichseparates the two channels from each other. If leakage is detected intesting each of the two channels an indication is given that the fixtureseparating the two channels is leaking.

[0011] Preferably, a first one of the fixtures connects to the secondopening and this fixture is exposed to atmosphere, and if leakage of airinto the channel is detected an indication is given that first one ofthe fixtures is leaking. If leakage of air into the channel is detectedan indication is given to a user that the channel failed the leakagetest. Such indication is preferably provided visually on a screen.

[0012] Preferably, the first opening is at a distal end of an endoscope.

[0013] In one aspect of the invention, the step of detecting for airleaking into the at least one channel comprises monitoring for airbubbles within the at least one channel. Such a monitor could comprise aturbidity meter or even a visual inspection by the user. Alternatively,the step of detecting for air leaking into the at least one channelcomprises monitoring a flow of the liquid through the at least onechannels.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The invention may take form in various components andarrangements of components and in various steps and arrangements ofsteps. The drawings are for purposes of illustrating preferredembodiments only, and are not to be construed as limiting the invention.

[0015]FIG. 1 is a front elevational view of a decontamination apparatusin accordance with the present invention;

[0016]FIG. 2 is a diagrammatic illustration of the decontaminationapparatus shown in FIG. 1, with only a single decontamination basinshown for clarity; and,

[0017]FIG. 3 is a cut-away view of an endoscope suitable for processingin the decontamination apparatus of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0018]FIG. 1 shows a decontamination apparatus for decontaminatingendoscopes and other medical devices which include channels or lumensformed therethrough; FIG. 2 shows the apparatus in block diagram form.The decontamination apparatus generally includes a first station 10 anda second station 12 which are at least substantially similar in allrespects to provide for the decontamination of two different medicaldevices simultaneously or in series. First and second decontaminationbasins 14 a, 14 b receive the contaminated devices. Each basin 14 a, 14b is selectively sealed by a lid 16 a, 16 b, respectively, preferably ina microbe-blocking relationship to prevent the entrance of environmentalmicrobes into the basins 14 a, 14 b during decontamination operations.The lids can include a microbe removal or HEPA air filter formed thereinfor venting.

[0019] A control system 20 includes one or more microcontrollers, suchas a programmable logic controller (PLC), for controllingdecontamination and user interface operations. Although one controlsystem 20 is shown herein as controlling both decontamination stations10, 12, those skilled in the art will recognize that each station 10, 12can include a dedicated control system. A visual display 22 displaysdecontamination parameters and machine conditions for an operator and atleast one printer 24 prints a hard copy output of the decontaminationparameters for a record to be filed or attached to the decontaminateddevice or its storage packaging. The visual display 22 is preferablycombined with a touch screen input device. Alternatively, a keypad orthe like is provided for input of decontamination process parameters andfor machine control. Other visual gauges 26 such as pressure meters andthe like provide digital or analog output of decontamination or medicaldevice leak testing data.

[0020]FIG. 2 diagrammatically illustrates one station 10 of thedecontamination apparatus. Those skilled in the art will recognize thatthe decontamination station 12 is preferably similar in all respects tothe station 10 illustrated in FIG. 2. However, the station 12 has notbeen shown in FIG. 2 for clarity. Further, the decontamination apparatuscan be provided with a single decontamination station or multiplestations.

[0021] The decontamination basin 14 a receives an endoscope 200 (seeFIG. 3) or other medical device therein for decontamination. Anyinternal channels of the endoscope 200 are connected with flush lines30. Each flush line 30 is connected to an outlet of a pump 32. The pumps32 are preferably peristaltic pumps or the like that pump fluid, such asliquid and air, through the flush lines 30 and any internal channels ofthe medical device. Specifically, the pumps 32 either can draw liquidfrom the basin 14 a through a filtered drain 34 and a first valve S1, orcan draw decontaminated air from an air supply system 36 through a valveS2. The air supply system 36 includes a pump 38 and a microbe removalair filter 40 that filters microbes from an incoming air stream. It ispreferable that each flush line 30 be provided with a dedicated pump 32to ensure adequate fluid pressure and to facilitate the individualmonitoring of the fluid pressure in each flush line 30. A pressureswitch or sensor 42 is in fluid communication with each flush line 30for sensing excessive pressure in the flush line. Any excessive pressuresensed is indicative of a partial or complete blockage, e.g., by bodilytissue or dried bodily fluids, in a device channel to which the relevantflush line 30 is connected. The isolation of each flush line 30 relativeto the others allows the particular blocked channel to be easilyidentified and isolated, depending upon which sensor 42 senses excessivepressure.

[0022] The basin 14 a is in fluid communication with a water source 50such as a utility or tap water connection including hot and cold inletsand a mixing valve 52 flowing into a break tank 56. A microbe removalfilter 54, such as a 0.2 μm or smaller absolute pore size filter,decontaminates the incoming water which is delivered into the break tank56 through the air gap to prevent backflow. A pressure type level sensor59 monitors liquid levels within the basin 14 a. An optional waterheater 53 can be provided if an appropriate source of hot water is notavailable.

[0023] The condition of the filter 54 can be monitored by directlymonitoring the flow rate of water therethrough or indirectly bymonitoring the basin fill time using a float switch or the like. Whenthe flow rate drops below a select threshold, this indicates a partiallyclogged filter element that requires replacement.

[0024] A basin drain 62 drains liquid from the basin 14 a through anenlarged helical tube 64 into which elongated portions of the endoscope200 can be inserted. The drain 62 is in fluid communication with arecirculation pump 70 and a drain pump 72. The recirculation pump 70recirculates liquid from the basin drain 62 to a spray nozzle assembly60 which sprays the liquid into the basin 14 a and onto the endoscope200. Coarse and fine screens 71 and 73, respectively, filter outparticles in the recirculating fluid. The drain pump 72 pumps liquidfrom the basin drain 62 to a utility drain 74. A level sensor 76monitors the flow of liquid from the pump 72 to the utility drain 74.The pumps 70 and 72 can be simultaneously operated such that liquid issprayed into the basin 14 a while it is being drained to encourage theflow of residue out of the basin and off of the device. Of course, asingle pump and a valve assembly could replace the dual pumps 70, 72.

[0025] An inline heater 80, with temperature sensors 82, downstream ofthe recirculation pump 70 heats the liquid to optimum temperatures forcleaning and disinfection. A pressure switch or sensor 84 measurespressure downstream of the circulation pump 70.

[0026] Detergent solution 86 is metered into the flow upstream of thecirculation pump 70 via a metering pump 88. A float switch 90 indicatesthe level of detergent available. Typically, only a small amount ofdisinfectant 92 is required. To more accurately meter this, a dispensingpump 94 fills a pre-chamber 96 under control of a hi/low level switch 98and of course the control system 20. A metering pump 100 meters aprecise quantity of disinfectant as needed.

[0027] Endoscopes and other reusable medical devices often include aflexible outer housing or sheath surrounding the individual tubularmembers and the like that form the interior channels and other parts ofthe device. This housing defines a closed interior space, which isisolated from patient tissues and fluids during medical procedures. Itis important that the sheath be maintained intact, without cuts or otherholes that would allow contamination of the interior space beneath thesheath. Therefore, the decontamination apparatus includes means fortesting the integrity of such as sheath.

[0028] An air pump, either the pump 38 or another pump 110, pressurizesthe interior space defined by the sheath of the device through a conduit112 and a valve S5. Preferably, a HEPA or other microbe-removing filter113 removes microbes from the pressurizing air. An overpressure switch114 prevents accidental over pressurization of the sheath. Upon fullpressurization, the valve S5 is closed and a pressure sensor 116 looksfor a drop in pressure in the conduit 112 which would indicate theescape of air through the sheath. A valve S6 selectively vents theconduit 112 and the sheath through an optional filter 118 when thetesting procedure is complete. An air buffer 120 smoothes out pulsationof pressure from the air pump 110.

[0029] Preferably, each station 10 and 12 each contain a drip basin 130and spill sensor 132 to alert the operator to potential leaks.

[0030] An alcohol supply 134 controlled by a valve S3 can supply alcoholto the channel pumps 32 after rinsing steps to assist in removing waterfrom the endoscope channels.

[0031] Flow rates in the supply lines 30 can be monitored via thechannel pumps 32 and the pressure sensors 42. The channels pumps 32 areperistaltic pumps which supply a constant flow. If one of the pressuresensors 42 detects too high a pressure the associated pump 32 cyclesoff. The flow rate of the pump 32 and its percentage on time provide areasonable indication of the flow rate in an associated line 30. Theseflow rates are monitored during the process to check for blockages inany of the endoscope channels. Alternatively, the decay in the pressurefrom the time the pump 32 cycles off can also be used to estimate theflow rate, with faster decay rates being associated with higher flowrates.

[0032] A more accurate measurement of flow rate in an individual channelmay be desirable to detect more subtle blockages. A metering tube 136having a plurality of level indicating sensors 138 fluidly connects tothe inputs of the channel pumps 32. One preferred sensor arrangementprovides a reference connection at a low point in the metering tube anda plurality of sensors 138 arranged vertically thereabove. By passing acurrent from the reference point through the fluid to the sensors 138 itcan be determined which sensors 138 are immersed and therefore determinethe level within the metering tube 136. Other level sensing techniquescan be applied here. By shutting valve S1 and opening a vent valve S7the channel pumps 32 draw exclusively from the metering tube. The amountof fluid being drawn can be very accurately determined based upon thesensors 138. By running each channel pump in isolation the flowtherethrough can be accurately determined based upon the time and thevolume of fluid emptied from the metering tube.

[0033] In addition to the input and output devices described above, allof the electrical and electromechanical devices shown are operativelyconnected to and controlled by the control system 20. Specifically, andwithout limitation, the switches and sensors 42, 59, 76, 84, 90, 98,114, 116, 132 and 136 provide input I to the microcontroller 28 whichcontrols the decontamination and other machine operations in accordancetherewith. For example, the microcontroller 28 includes outputs O thatare operatively connected to the pumps 32, 38, 70, 72, 88, 94, 100, 110,the valves S1-S7, and the heater 80 to control these devices foreffective decontamination and other operations.

[0034] Turning also to FIG. 3, an endoscope 200 has a head part 202, inwhich openings 204 and 206 are formed, and in which, during normal useof the endoscope 200, an air/water valve and a suction valve arearranged. A flexible insertion tube 208 is attached to the head part202, in which tube a combined air/water channel 210 and a combinedsuction/biopsy channel 212 are accommodated.

[0035] A separate air channel 213 and water channel 214, which at thelocation of a joining point 216 merge into the air/water channel 210,are arranged in the head part 202. Furthermore, a separate suctionchannel 217 and biopsy channel 218, which at the location of the joiningpoint 220 merge into the suction/biopsy channel 212, are accommodated inthe head part 202.

[0036] In the head part 202, the air channel 213 and the water channel214 open into the opening 204 for the air/water valve. The suctionchannel 217 opens into the opening 206 for the suction valve.Furthermore, a flexible feed hose 222 connects to the head part 202 andaccommodates channels 213′, 214′ and 217′ which via the openings 204 and206, are connected to the air channel 213, the water channel 214 and thesuction channel 217, respectively. In practice, the feed hose 222 isalso referred to as the light-conductor casing.

[0037] The mutually connecting channels 213 and 213′, 214 and 214′, 217and 217′ will be referred to below overall as the air channel 213, thewater channel 214 and the suction channel 217.

[0038] A connection 226 for the air channel 213, connections 228 and 228a for the water channel 214 and a connection 230 for the suction channel217 are arranged on the end section 224 (also referred to as the lightconductor connector) of the flexible hose 222. When the connection 226is in use, connection 228 a is closed off. A connection 232 for thebiopsy channel 218 is arranged on the head part 202.

[0039] A channel separator 240 is shown inserted into the openings 204and 206. It comprises a body 242, and plug members 244 and 246 whichocclude respectively openings 204 and 206. A coaxial insert 248 on theplug member 244 extends inwardly of the opening 204 and terminates in anannular flange 250 which occludes a portion of the opening 204 toseparate channel 213 from channel 214. By connecting the lines 30 to theopenings 226, 228, 228 a, 230 and 232, liquid for cleaning anddisinfection can be flowed through the endoscope channels 213, 214, 217and 218 and out of a distal tip 252 of the endoscope 200 via channels210 and 212. The channel separator 240 ensures the such liquid flows allthe way through the endoscope 200 without leaking out of openings 204and 206 and isolates channels 213 and 214 from each other so that eachhas its own independent flow path. One of skill in the art willappreciate that various endoscopes having differing arrangements ofchannels and openings will likely require modifications in the channelseparator 240 to accommodate such differences while occluding ports inthe head 202 and keeping channels separated from each other so that eachchannel can be flushed independently of the other channels. Otherwise ablockage in one channel might merely redirect flow to a connectedunblocked channel.

[0040] A leakage port 254 on the end section 224 leads into an interiorportion 256 of the endoscope 200 and is used to check for the physicalintegrity thereof, namely to ensure that no leakage has formed betweenany of the channels and the interior 256 or from the exterior to theinterior 256.

[0041] The cleaning and sterilization cycle in detail comprises thefollowing steps.

[0042] Step 1. Open the Lid

[0043] Pressing a foot pedal (not shown) opens the basin lid 16 a. Thereis a separate foot pedal for each side. If pressure is removed from thefoot pedal, the lid motion stops.

[0044] Step 2. Position and Connect the Endoscope

[0045] The insertion tube 208 of the endoscope 200 is inserted into thehelical circulation tube 64. The end section 224 and head section 202 ofthe endoscope 200 are situated within the basin 14 a, with the feed hose222 coiled within the basin 14 a with as wide a diameter as possible.

[0046] The flush lines 30, preferably color-coded, are attached, oneapiece, to the endoscope openings 226, 228, 228 a, 230 and 232. The airline 112 is also connected to the connector 254. A guide located on theon the station 10 provides a reference for the color-coded connections.

[0047] Step 3. Identify the User, Endoscope, and Specialist to theSystem

[0048] Depending on the customer-selectable configuration, the controlsystem 20 may prompt for user code, patient ID, endoscope code, and/orspecialist code. This information may be entered manually (through thetouch screen) or automatically such as by using an attached barcode wand(not shown).

[0049] Step 4. Close the Basin Lid

[0050] Closing the lid 16 a preferably requires the user to press ahardware button and a touch-screen 22 button simultaneously (not shown)to provides a fail-safe mechanism for preventing the user's hands frombeing caught or pinched by the closing basin lid 16 a. If either thehardware button or software button is released while the lid 16 a is inthe process of closing the motion stops.

[0051] Step 5. Start Program

[0052] The user presses a touch-screen 22 button to begin thewashing/disinfection process.

[0053] Step 6. Pressurize the Endoscope Body and Measure the Leak Rate

[0054] The air pump is started and pressure within the endoscope body ismonitored. When pressure reaches 250 mbar, the pump is stopped, and thepressure is allowed to stabilize for 6 seconds. If pressure has notreached 250 mbar in 45 seconds the program is stopped and the user isnotified of the leak. If pressure drops to less than 100 mbar during the6-second stabilization period, the program is stopped and the user isnotified of the condition.

[0055] Once the pressure has stabilized, the pressure drop is monitoredover the course of 60 seconds. If pressure drops more than 10 mbarwithin 60 seconds, the program is stopped and the user is notified ofthe condition. If the pressure drop is less than 10 mbar in 60 seconds,the system continues with the next step. A slight positive pressure isheld within the endoscope body during the rest of the process to preventfluids from leaking in.

[0056] Step 7. Check Connections

[0057] A second leak test checks the adequacy of connection to thevarious ports 226, 228, 228 a, 230, 232 and the proper placement of thechannel separator 240. A quantity of water is admitted to the basin 14 aso as to submerge the distal end of the endoscope in the helical tube64. Valve S1 is closed and valve S7 opened and the pumps 32 are run inreverse to draw a vacuum and to ultimately draw liquid into theendoscope channels 210 and 212. The pressure sensors 42 are monitored tomake sure that the pressure in any one channel does not drop by morethan a predetermined amount in a given time frame. If it does, it likelyindicates that one of the connections was not made correctly and air isleaking into the channel. In any event, in the presence of anunacceptable pressure drop the control system 20 will cancel the cyclean indicate a likely faulty connection, preferably with an indication ofwhich channel failed.

[0058] Pre-Rinse

[0059] The purpose of this step is to flush water through the channelsto remove waste material prior to washing and disinfecting the endoscope200.

[0060] Step 8. Fill Basin

[0061] The basin 14 a is filled with filtered water and the water levelis detected by the pressure sensor 59 below the basin 14 a.

[0062] Step 9. Pump Water through Channels

[0063] The water is pumped via the pumps 32 through the interior of thechannels 213, 214, 217, 218, 210 and 212 directly to the drain 74. Thiswater is not recirculated around the exterior surfaces of the endoscope200 during this stage.

[0064] Step 10. Drain

[0065] As the water is being pumped through the channels, the drain pump72 is activated to ensure that the basin 14 a is also emptied. The drainpump 72 will be turned off when the drain switch 76 detects that thedrain process is complete.

[0066] Step 11. Blow Air through Channels

[0067] During the drain process sterile air is blown via the air pump 38through all endoscope channels simultaneously to minimize potentialcarryover.

[0068] Wash

[0069] Step 12. Fill Basin

[0070] The basin 14 a is filled with warm water (35° C.). Watertemperature is controlled by controlling the mix of heated and unheatedwater. The water level is detected by the pressure sensor 59.

[0071] Step 13. Add Detergent

[0072] The system adds enzymatic detergent to the water circulating inthe system by means of the peristaltic metering pump 88. The volume iscontrolled by controlling the delivery time, pump speed, and innerdiameter of the peristaltic pump tubing.

[0073] Step 14. Circulate Wash Solution

[0074] The detergent solution is actively pumped throughout the internalchannels and over the surface of the endoscope 200 for a predeterminedtime period, typically of from one to five minutes, preferably aboutthree minutes, by the channel pumps 32 and the external circulation pump70. The inline heater 80 keeps the temperature at about 35° C.

[0075] Step 15. Start Block Test

[0076] After the detergent solution has been circulating for a couple ofminutes, the flow rate through the channels is measured. If the flowrate through any channel is less than a predetermined rate for thatchannel, the channel is identified as blocked, the program is stopped,and the user is notified of the condition. The peristaltic pumps 32 arerun at their predetermined flow rates and cycle off in the presence ofunacceptably high pressure readings at the associated pressure sensor42. If a channel is blocked the predetermined flow rate will trigger thepressure sensor 42 indicating the inability to adequately pass this flowrate. As the pumps 32 are peristaltic, their operating flow ratecombined with the percentage of time they are cycled off due to pressurewill provide the actual flow rate. The flow rate can also be estimatedbased upon the decay of the pressure from the time the pump 32 cyclesoff.

[0077] Step 16. Drain

[0078] The drain pump 72 is activated to remove the detergent solutionfrom the basin 14 a and the channels. The drain pump 72 turns off whenthe drain level sensor 76 indicates that drainage is complete.

[0079] Step 17.

[0080] Blow Air

[0081] During the drain process sterile air is blown through allendoscope channels simultaneously to minimize potential carryover.

[0082] Rinse

[0083] Step 18. Fill Basin

[0084] The basin 14 a is filled with warm water (35° C.). Watertemperature is controlled by controlling the mix of heated and unheatedwater. The water level is detected by the pressure sensor 59.

[0085] Step 19. Rinse

[0086] The rinse water is circulated within the endoscope channels (viathe channel pumps 32) and over the exterior of the endoscope 200 (viathe circulation pump 70 and the sprinkler arm 60) for 1 minute.

[0087] Step 20. Continue Block Test

[0088] As rinse water is pumped through the channels, the flow ratethrough the channels is measured and if it falls below the predeterminedrate for any given channel, the channel is identified as blocked, theprogram is stopped, and the user is notified of the condition.

[0089] Step 21. Drain

[0090] The drain pump is activated to remove the rinse water from thebasin and the channels.

[0091] Step 22.

[0092] Blow Air

[0093] During the drain process sterile air is blown through allendoscope channels simultaneously to minimize potential carryover.

[0094] Step 23. Repeat Rinse

[0095] Steps 18 through 22 are repeated to ensure maximum rinsing ofenzymatic detergent solution from the surfaces of the endoscope and thebasin.

[0096] Disinfect

[0097] Step 24. Fill Basin

[0098] The basin 14 a is filled with very warm water (53° C.). Watertemperature is controlled by controlling the mix of heated and unheatedwater. The water level is detected by the pressure sensor 59. During thefilling process, the channel pumps 32 are off in order to ensure thatthe disinfectant in the basin is at the in-use concentration prior tocirculating through the channels.

[0099] Step 25. Add Disinfectant

[0100] A measured volume of disinfectant 92, preferably CIDEX OPAorthophalaldehyde concentrate solution, available from AdvancedSterilization Products division Ethicon, Inc., Irvine, Calif., is drawnfrom the disinfectant metering tube 96 and delivered into the water inthe basin 14 a via the metering pump 100. The disinfectant volume iscontrolled by the positioning of the fill sensor 98 relative to thebottom of the dispensing tube. The metering tube 96 is filled until theupper level switch detects liquid. Disinfectant 92 is drawn from themetering tube 96 until the level of the disinfectant in the meteringtube is just below the tip of the dispensing tube. After the necessaryvolume is dispensed, the metering tube 96 is refilled from the bottle ofdisinfectant 92. Disinfectant is not added until the basin is filled, sothat in case of a water supply problem, concentrated disinfectant is notleft on the endoscope with no water to rinse it. While the disinfectantis being added, the channel pumps 32 are off in order to insure that thedisinfectant in the basin is at the in-use concentration prior tocirculating through the channels.

[0101] Step 26. Disinfect

[0102] The in-use disinfectant solution is actively pumped throughoutthe internal channels and over the surface of the endoscope, ideally fora minimum of 5 minutes, by the channel pumps and the externalcirculation pump. The temperature is controlled by the in-line heater 80to about 52.5° C.

[0103] Step 27. Flow Check

[0104] During the disinfection process, flow through each endoscopechannel is verified by timing the delivering a measured quantity ofsolution through the channel. Valve S1 is shut, and valve S7 =opened,and in turn each channel pump 32 delivers a predetermined volume to itsassociated channel from the metering tube 136. This volume and the timeit takes to deliver provides a very accurate flow rate through thechannel. Anomalies in the flow rate from what is expected for a channelof that diameter and length are flagged by the control system 20 and theprocess stopped.

[0105] Step 28. Continue Block Test

[0106] As disinfectant in-use solution is pumped through the channels,the flow rate through the channels is also measured as in Step 15.

[0107] Step 29. Drain

[0108] The drain pump 72 is activated to remove the disinfectantsolution from the basin and the channels.

[0109] Step 30. Blow Air

[0110] During the drain process sterile air is blown through allendoscope channels simultaneously to minimize potential carryover.

[0111] Final Rinse

[0112] Step 31. Fill Basin

[0113] The basin is filled with sterile warm water (45° C.) that hasbeen passed through a 0.2μ filter.

[0114] Step 32. Rinse

[0115] The rinse water is circulated within the endoscope channels (viathe channel pumps 32) and over the exterior of the endoscope (via thecirculation pump 70 and the sprinkler arm 60) for 1 minute.

[0116] Step 33. Continue Block Test

[0117] As rinse water is pumped through the channels, the flow ratethrough the channels is measured as in Step 15.

[0118] Step 34. Drain

[0119] The drain pump 72 is activated to remove the rinse water from thebasin and the channels.

[0120] Step 35. Blow Air

[0121] During the drain process sterile air is blown through allendoscope channels simultaneously to minimize potential carryover.

[0122] Step 36. Repeat Rinse

[0123] Steps 31 through 35 are repeated two more times (a total of 3post-disinfection rinses) to ensure maximum reduction of disinfectantresiduals from the endoscope 200 and surfaces of the reprocessor.

[0124] Final Leak Test

[0125] Step 37. Pressurize the Endoscope Body and Measure Leak Rate

[0126] Repeat Step 6.

[0127] Step 38. Indicate Program Completion

[0128] The successful completion of the program is indicated on thetouch screen.

[0129] Step 39. De-Pressurize the Endoscope

[0130] From the time of program completion to the time at which the lidis opened, pressure within the endoscope body is normalized toatmospheric pressure by opening the vent valve S5 for 10 seconds everyminute.

[0131] Step 40. Identify the User

[0132] Depending on customer-selected configuration, the system willprevent the lid from being opened until a valid user identification codeis entered.

[0133] Step 41. Store Program Information

[0134] Information about the completed program, including the user ID,endoscope ID, specialist ID, and patient ID are stored along with thesensor data obtained throughout the program.

[0135] Step 42. Print Program Record

[0136] If a printer is connected to the system, and if requested by theuser, a record of the disinfection program will be printed.

[0137] Step 43. Remove the Endoscope

[0138] Once a valid user identification code has been entered, the lidmay be opened (using the foot pedal as in step 1, above). The endoscopeis then disconnected from the flush lines 30 and removed from the basin14 a. The lid can then be closed using both the hardware and softwarebuttons as described in step 4, above.

[0139] The invention has been described with reference to the preferredembodiments. Obviously, modifications and alterations will occur toothers upon reading and understanding the preceding detaileddescription. It is intended that the invention be construed as includingall such modifications and alterations insofar as they come within thescope of the appended claims or the equivalents thereof.

What is claimed is:
 1. A method of detecting proper connection offixtures to one or more channels in an endoscope, the endoscope having afirst opening into at least of the channels, the method comprising thesteps of: placing the endoscope at the first opening into a liquid;having a gas within the at least one channel; drawing a vacuum on thegas through a second opening into the at least one channel and therebydrawing some of the liquid into the at least one channel; detecting forair leaking into the at least one channel.
 2. A method according toclaim 1 wherein the step of detecting for air leaking into the at leastone channel comprises monitoring the pressure within the at least onechannel.
 3. A method according to claim 2 wherein the pressure ismonitored and if it falls below a given amount in a given time period anindication is given that the at least one channel is leaking.
 4. Amethod according to claim 1 wherein the endoscope has at least twochannels and where one of the fixtures separates two of the channelsfrom each other and further comprising the step of individually testingeach of the two channels whereby to detect gas leaking past the fixturewhich separates the two channels from each other.
 5. A method accordingto claim 4 wherein if leakage is detected in testing each of the twochannels an indication is given that the fixture separating the twochannels is leaking.
 6. A method according to claim 1 wherein a firstone of the fixtures connects to the second opening and this fixture isexposed to atmosphere, and if leakage of air into the at least onechannel is detected an indication is given that first one of thefixtures is leaking.
 7. A method according to claim 1 wherein if leakageof air into the at least one channel is detected an indication is givento a user that the at least one channel failed the leakage test.
 8. Amethod according to claim 7 wherein the indication is provided visuallyon a screen.
 9. A method according to claim 1 wherein the first openingis at a distal end of an endoscope.
 10. A method according to claim 1wherein the step of detecting for air leaking into the at least onechannel comprises monitoring for air bubbles within the at least onechannel.
 11. A method according to claim 1 wherein the step of detectingfor air leaking into the at least one channel comprises monitoring aflow of the liquid through the at least one channels.